Does time exist? The answer to this question may seem obvious: of course, it does! Just look at a calendar or a clock.
But developments in physics suggest the non-existence of time is an open possibility and one that we should take seriously.
Published in the recent book: "Out of Time -- A Philosophical Study of Timelessness," two physics professors, Samuel Baron, Kristie Miller,
and philosophy professor Jonathan Tallant provide the first systematic analysis of the idea that time does not exist in modern philosophy.
They employ a naturalistic methodology that combines philosophy with scientific investigation
and provide a careful study of the relationship between time, causation, and agency.
According to physicists and philosophers, time might not exist.
The idea that time does not exist is, for many, unthinkable: time must exist. Almost every experience we have tells us so.
There has been plenty of debate around what time is like, but not whether it exists.
The goal of this book is to make the absence of time thinkable. Time might not exist.
Beginning with an empirically flavored examination of the 'folk' concept , the book explores the implications for our understanding of agency
and how our best physics and best metaphysics are compatible with a timeless conception of reality.
Physics is in crisis.
We have explained the universe with two wildly successful physical theories: general relativity and quantum mechanics, for the past century.
Quantum mechanics describes how things work in the incredibly tiny world of particles and particle interactions.
General relativity describes the big picture of gravity and how objects move.
Both theories work exceptionally well in their own right, but the two are thought to conflict.
Though the exact nature of the conflict is controversial,
scientists generally agree both theories need to be replaced with a new, more general approach.
Physicists want to produce a theory of “quantum gravity” that replaces general relativity and quantum mechanics
while capturing the extraordinary success of both.
Such a theory would explain how gravity’s big picture works at the miniature scale of particles.
It turns out that producing a theory of quantum gravity is extraordinarily difficult.
One attempt to overcome the conflict between the two theories is string theory.
String theory replaces particles with strings vibrating in as many as 11 dimensions.
However, string theory faces further difficulty.
String theories provide a range of models that describe a universe broadly like our own, and they don’t really make any precise predictions
that can be tested by experiments to figure out which model is the right one.
In the 1980s and 1990s, many physicists became dissatisfied with string theory
and came up with a range of new mathematical approaches to quantum gravity.
One of the most prominent of these is loop quantum gravity,
which proposes that the fabric of space and time is made of a network of tiny discrete chunks, or “loops.”
One of the remarkable aspects of loop quantum gravity is that it eliminates time entirely.
Loop quantum gravity is not alone in abolishing time: several other approaches also seem to remove time as a fundamental aspect of reality.
So we know we need a new physical theory to explain the universe and that this theory might not feature time.
Suppose such a theory turns out to be correct. Would it follow that time does not exist?
It’s complicated, and it depends on what we mean by existing.
Theories of physics don’t include any tables, chairs, or people, yet we still accept that tables, chairs, and people exist.
Why? Because we assume that such things exist at a higher level than the level described by physics.
We say that tables, for example, “emerge” from an underlying physics of particles whizzing around the universe.
But while we have a pretty good sense of how a table might be made out of fundamental particles,
we have no idea how time might be “made out of” something more fundamental.
So unless we can come up with a good account of how time emerges, it is not clear we can simply assume time exists.
Time might not exist at any level.
Saying that time does not exist at any level is like saying there are no tables.
Trying to get by in a world without tables might be challenging, but managing in a world without time seems positively disastrous.
Our entire lives are built around time. We plan for the future based on what we know about the past.
We hold people morally accountable for their past actions to reprimand them later on.
We believe ourselves to be agents (entities that can do things)
partly because we can plan to act in a way that will bring about changes in the future.
The discovery that time does not exist would seem to bring the entire world to a grinding halt.
There is a way out of the mess.
While physics might eliminate time, it seems to leave causation intact: the sense in which one thing can bring about another.
Perhaps what physics is telling us, then, is that causation and not time is the essential feature of our universe.
If that’s right, then the agency can still survive. It is possible to reconstruct a sense of agency entirely in causal terms.
The discovery that time does not exist may have no direct impact on our lives, even while it propels physics into a new era.